Pentax K-1 Mark II and Blotches of Magenta — The Remedy
I have been spoiled with amazing dynamic range on both the K-1 and the 645Z when shooting iso 100 which is my preferred iso setting. It has been possible to underexpose with for instance four stops and yet brightening the darkest shadows without any issues save a little grain now and then, but no color cast. However, when I got the K-1 Mark II I immediately found that the shadows turned magenta when pushing the files at iso 100. There is a very simple remedy for this, but let us have a look at few examples first.
It is also worth noting that for me color work is vital when editing my images, and I go to great lengths in order to achieve colors and a color harmony that is pleasant in my eyes. Thus, my eyes are well trained and I may spot unwanted colors which others perhaps find unproblematic.
The following is an image straight out of camera at iso 100 — it is exposed for the highlights:
After some adjustments in Lightroom:
It turns out, however, that shooting iso 125 is the solution if the camera produces magenta cast in the shadows at iso 100.
Go to the C1 (Custom) menu and first set EV steps to 1/3 in C1–1 and next in C1–2 set iso steps to equal EV stops. We now have iso 100, 125, 160, 200, 250, 320 etc available.
The next straight out of camera image is shot at iso 125.
After a few Lightroom adjustments — the deepest shadows are very clean color wise:
The finished image:
